Jan. 14 (Bloomberg) -- Federal Reserve Chairman Ben S.
Bernanke said the benefits of quantitative easing may vary
through time and the central bank is continuing to monitor the
impact of its bond purchases.

“So far, we think we are getting some effect, it is kind
of early,” Bernanke said today. “We are going to continue to
assess how effective” the program is “because it is possible
that as you move through time and the situation changes that the
impact of these tools could vary.”

Bernanke made the comments in a discussion with Dean Susan
M. Collins at the University of Michigan’s Gerald R. Ford School
of Public Policy. The 59-year-old Fed chairman is using
unprecedented tools including bond purchases and communication
policies to spur economic growth and cut U.S. unemployment,
which was 7.8 percent last month or slightly below its 8.1
percent average for 2012.

“We will continue to evaluate,” Bernanke said. “We will
be assessing the impact of our actions on financial market
conditions and looking to see how those link up to developments
in labor markets and the broader economy.”

The Federal Open Market Committee last month linked the
outlook for its main interest rate to unemployment and inflation
for the first time, and said that, in addition to buying $40
billion in mortgage bonds each month, it will expand its asset
purchase program by purchasing $45 billion a month of Treasury
securities starting in January.

Fed officials said last month they will keep rates near
zero as long as the jobless rate is above 6.5 percent and
inflation is forecast to be 2.5 percent or less. Previously,
they said they would keep rates low through at least mid-2015.